Improvements in and relating to resinous compositions derived from polyhydric alcohols and polybasic acids



positions of the alkyd type.

Patented UNI-TED STAT 1,975,569 a Y masmous COMPOSITION Walter w.Durantand Paul 11. Scrutchfield, Pittsfield, Mass., assignors to:General Electric Company, a, corporation of New York N Drawing.

8 Claims.

The present invention relates to resinous compositions and moreparticularly to resinous com- Specifically, this invention is concernedwith a coating composition embodying a resin of the alkyd type and whichis especially useful in coating fibrous material, such .ascloth, paperand the like in order to impart thereto and provide thereon a fiexible,tough film of good dielectric value, unaflected by mineral oil or bypetroleum or aromatic solvents.

. In accordance with our invention we have found that we can prepare acoating composition which is especially adapted to the manufacture ofvar- Ap'plication February 26, 1931, Serial No. 518,497

heated is not fixed'at 250 0. It may vary from 230 C. to 270 C. Theresin is dissolved in a suitable 'so1vent, for example, acetone, ethylcellosolve, butyl c'arbitol, cellosolve acetate, ethyl acetate,furfural, toluol, alcohol, or a suitable combination oflthese.

A varnish such as described above makes a very' nished czinbricemployedfor'electrigal jnsulation varnish in reasonably thinillms-is about 4hours 5 purposes but which is, 'h'tfivevf not limited to such use. Itmay' be used wherever an oil resistant, very flexible varnished clothis-desired; for example, as diaphragms for gasoline pumps or Mgrpressure typej'oil level indicators for storage ream For;-aconsideration of what we believe to be noveland our invention attentionis directed to the following specification and the claims ap-'.pended'thereto.

Alkyd resins comprise those complexes resulting primarily from theinteraction of a polyhydric alcohol, such as glycerine, and a polybasicacid, such as phthalic acid or its anhydride. For carrying out thepurposes of our invention we have found that if we react with thepolyhydric alcohol and polybasic acid, a dihydric' alcoholand a dibasicaliphatic acid, together with a natural resin or resinic acidderivedtherefrom, such as abietic acid, and a vegetable oil, preferablya drying oil, we obtain a resinous composition admirably suited forproducing a liquid coating composition which yields on curing a tough,very flexible, oil resistant, alkali and acid resistant, non-solublefilm of good dielectric value.

Our invention will be best understood by reference to the followingspecific examples which are merely illustrative in nature.

One method of producing a liquid coating com position of our inventionis as follows:

at 135 to 140 C. I

, The proportions of resinous ingredients may be varied and in order toillustrate this the following example is given. This resinouscomposition, preparedin a manner similar to that given above, isslightly less flexible than the first composition but has, however,asomewhat faster curing time and gives a harder and tougher film.

Example 2 p Parts-by weight Phthalic anhydride 235 Glycerine r 118Succinic acid .235

Ethylene glycol 230 'Rosin ....';T 200 Chinawood oil -80 Another exampleof the preparation of a resin in accordance with the method outlined inExample 1 is the following:

Example 3 Parts by weight Phthalic anhydride 426 Glycerine 258 Ethyleneglycol 484 Succinic acid 912 Dammar gum 400 Chinawood oil 160 A secondmethod of preparing resinous com- 7 Exam 161 positions in accordancewith our 1nvention is p Parts by Weight illustrated by the followingexample:

Phthalic anhydride 213 I Example 4 Glycer ne 129 Parts by weightSucc1n1c and 6 'Phthalic anhydride 852 Ethylene gly 242 Ethylene glycol356 Rosin 200 Rosin 800 Chinawood i V 80 Glycerol 180 The aboveingredients are mixed together and are h t d t apprgximately 210 3,, t t

heated to 250 C. as quickly as possible. and held at this temperatureuntil the resin has become clear and until the acid number is less than25 milligrams of NaOH per gram of resin. The temperature to which theingredients are initially ring, and 320 parts by weight of Chinawood oilare added. The temperature of the mass is now 1168 parts 'by' weight of.succinic acid are now Glycerine added. The resinous mass is againheated until it is clear. 336 parts by weight of glycerine and 648 partsby weight of succinic acid are added and the mass cooked until it isclear.

Still another method of producing the resinous compositions of ourinvention is illustrated by the following example:

Example 5 Parts by weight Abietic acid 800 (50% excess) Phthalicanhydride 852 Ethylene glycol 965 Linseed oil fatty acids The aboveingredients are heated under reflux to 175 to 180 C. for approximately30 minutes and 320 parts by weight of Chinawood oil are added in fourparts. The mass is then cooked at 240 C. until it is clear. 1820 partsby weight of succinic acid are added and the mass cooked until the resinis formed. The excess glycerine is removed by vacuum distillation. Thismethod gives a resin with a lower acid number than the first methoddescribed above.

It is of courseunderstood that our invention is not limited to thespecific ingredients named above in the illustrative examples. Forexample, 30*35 dihydric al cohols wenTay employ suchalcohols aspropylene glycol, diethylene glycol, tetramethylene glycol and the like;as dibasic aliphatic acids we may use such acids as malic, maleic,fumaric, glutaric, adipic, pimelic, suberic acids and the like. Otherpolybasic acids besides phthalic acid or its anhydride,'and polyhydricalcohols other than glycerine, especially those having three or morehydroxyl groups in the molecule, may be employed in preparing an alkydresin. Instead of rosin, other natural resins or the acids derivedtherefrom, for example, dammar, kauri, copal and the like may be used;and in place of Chinawood oil, any vegetable oil, preferably a dryingoil, such as linseeed oil, perilla oil, soya bean oil and the like maybe used.

What we claim as new and desire to secure by Letters Patent of theUnited States is:

1. A resinous composition comprising the product of reaction of phthalicanhydride, glycerine, succinic acid, ethylene glycol, abietic acid andChinawood oil.

2. A liquid coating composition comprising the product of reaction ofphthalic anhydride, glycerine, succinic acid, ethylene glycol, rosin andChinawood oil dissolved in a suitable solvent.

3. A resinous composition comprising the product of reaction of apolybasic aromatic acid, a polyhydric alcohol having three or morehydroxyl groups in the molecule, a dibasic aliphatic acid, a dihydricalcohol, a natural resin or the acid derived therefrom, and a vegetableoil.

4. A liquid coating composition comprising the product of reaction of apolybasicaromatic acid, a polyhydric alcohol having three or morehydroxyl groups in the molecule, a dibasic aliphatic acid, a. dihydricalcohol, a natural resin or the acid derived therefrom, and a vegetableoil, dissolved in a suitable solvent.

5. The process which comprises reacting a polybasic aromatic acid, adibasic aliphatic acid, a dihydric alcohol, a natural resin or the acidderived therefrom and a vegetable oil in the presence of an excess ofpolyhydric alcohol having three or more hydroxyl groups in the moleculeuntil a resinous composition is formed and removing the excesspolyhydric alcohol from the resinous composition.

6. The process which comprises reacting phthalic anhydride, succinicacid, ethylene glycol, abietic acid and vegetable oil in the presence ofan excess of glycerine until a resinous composition is formed andremoving the excess glycerine from theresinous compcsitionby vacuumdistillationT 'l. The process which comprises heating a mixturecomprising abietic acid, phthalic anhydride and ethylene glycol with anexcess of glycerine under a refiux'to 71175 to 180 C. for approximately30 minutes, addingbhinawood oilthereto, ne'ating the mass at 240 C.until it is clear, adding succinic acid and heating until a resin isformed and removing the excess glycerine from the resin by vacuumdistillation.

8. The process which comprises heating a mixture comprising 800 parts byweight abietic acid,

770 parts by weight glycerine,852 parts by weight

